Association of serum anti-centromere protein F antibodies with clinical response to infliximab in patients with rheumatoid arthritis: A prospective study.

BACKGROUND: One-third of rheumatoid arthritis (RA) patients demonstrate no clinical improvement after receiving tumor necrosis factor inhibitors (TNFi). The presence of serum autoantibodies is a hallmark in RA and may provide information on future response to treatment. The aim of this prospective study was to search for novel serum autoantibodies useful to predict clinical response to TNFi. METHODS: The autoantibody repertoire was profiled on RA patients treated with TNFi as a first line of biologic therapy (N = 185), who were recruited in three independent cohorts. The presence and levels of autoantibodies in serum at baseline were analysed in association with the clinical response after 24 weeks follow-up. A multiplex bead array built using antigens selected from an initial untargeted screening was employed to identify the autoantibodies on a discovery cohort (N = 50) and to verify and validate the results on verification (N = 61) and validation (N = 74) cohorts. Non-parametric tests, meta-analysis and Receiver Operating Curves (ROC) were performed in order to assess the clinical relevance of the observed findings. RESULTS: Novel autoantibodies were associated with the clinical response to TNFi, showing different reactivity profiles among the different TNFi. The baseline levels of IgG antibodies against Centromere protein F (CENPF), a protein related to cell proliferation, were significantly (p<0.05) increased in responders (N = 111) to infliximab (IFX) compared to non-responders (N = 44). The addition of anti-CENPF antibodies to demographic and clinical variables (age, sex, DAS28-ESR) resulted in the best model to discriminate responders, showing an area under the curve (AUC) of 0.756 (95% CI [0.639-0.874], p = 0.001). A further meta-analysis demonstrated the significant association of anti-CENPF levels with the patient's subsequent response to IFX, showing a standardized mean difference (SMD) of -0.65 (95% CI [-1.02;-0. 27], p = 0.018). CONCLUSIONS: Our study reveals for the first time the potential of circulating anti-CENPF antibodies to predict the clinical response to IFX before starting the treatment. This finding could be potentially useful to guide therapeutic decisions and may lead to further studies focusing on the role of CENPF on RA pathology.

The Impact of Comorbidity on Patient-Reported Outcomes in Psoriatic Arthritis: A Systematic Literature Review.

INTRODUCTION: A systematic literature review was conducted with the aim to analyse the impact of comorbidity on patient-reported outcomes (PROs) in patients with psoriatic arthritis (PsA). METHODS: A sensitive search strategy of the Medline, Embase and the Cochrane Library (up to March 2019) was applied to retrieve studies for inclusion in this systematic literature review. Abstracts of the ACR and EULAR scientific meetings were also searched. The selection criteria were: (1) patients with PsA (population) with a comorbidity (intervention) and (2) report of any impact of the comorbidity on PROs. Systematic literature reviews, randomized controlled trials and observational were included in this systematic literature review. Two of the authors selected the articles and collected the data. RESULTS: Eighteen articles were included in this systematic literature review, with most being cross-sectional studies that included more than 9000 patients with PsA. Some studies analysed the impact of an individual comorbidity, such as fibromyalgia (FM), and in others the analysis was according to the number of comorbidities. The most frequently analysed PROs were function, quality of life and fatigue. Analysis of the studies included in the review showed that patients with a higher number of comorbidities and/or more severe comorbidities reported worse impacts of their disease on function, patient's global assessment (PGA), pain, fatigue, work disability and quality of life. Specifically, FM had a negative impact on the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), function, quality of sleep and quality of life; anxiety and depression had a negative impact on function and fatigue; metabolic syndrome had a negative impact on BASDAI, function, PGA and quality of life; obesity had a negative impact on function and pain; smoking (current and ex-smokers) had a negative impact on pain, function, fatigue, quality of life and overall health; alcohol intake had a negative impact on pain, function, fatigue, quality of life and overall health. CONCLUSIONS: The prevalence and impact of medical comorbidity on PROs are very high in patients with PsA.

Validity of the bath ankylosing spondylitis disease activity index for the evaluation of disease activity in axial psoriatic arthritis.

OBJECTIVE: To assess the validity of the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) for the evaluation and definition of disease activity of axial psoriatic arthritis (PsA). METHODS: Fifty-four peripheral PsA, 46 axial PsA, and 103 primary ankylosing spondylitis (AS) patients were assessed. Patients were classified as having axial PsA if they had grade 2 or higher unilateral sacroiliitis in the presence of spinal symptoms. The 3 groups of patients were evaluated using several measurements for AS. Assessments of acceptability, data quality, internal consistency, construct validity, and responsiveness of the BASDAI were undertaken. Disease activity of the disease was assessed in peripheral PsA and axial PsA patients using the BASDAI, and compared with those with AS. RESULTS: For peripheral PsA patients, the Cronbach's alpha for the BASDAI was 0.783, for axial PSA patients it was 0.647, and for AS patients it was 0.786. The analysis of convergent validity showed that in peripheral PsA and axial PsA patients, the BASDAI was significantly correlated with other subjective disease activity parameters. For responsiveness, no association was found between changes in the BASDAI and changes in disease activity either in peripheral PsA or in axial PsA. BASDAI scores were similar in axial PsA and AS. Axial PsA patients with a BASDAI score >4 cm showed significant differences with peripheral PsA in terms of disease activity and were very similar to patients with AS. CONCLUSION: The BASDAI performed similarly in evaluating disease activity in both axial and peripheral PsA. The BASDAI does not seem to be a good index for evaluating disease activity in axial PsA.

Evaluation of ankylosing spondylitis spinal mobility measurements in the assessment of spinal involvement in psoriatic arthritis.

OBJECTIVE: To determine the clinical usefulness of spinal mobility measurements used for ankylosing spondylitis (AS) to assess spinal involvement in patients with psoriatic arthritis (PsA). METHODS: We assessed 100 patients with PsA and 103 patients with AS. Patients were classified as having axial PsA if they had grade 2 or higher unilateral sacroiliitis in the presence of spinal symptoms. All PsA patients, without taking the degree of joint involvement into consideration, were evaluated using several measurements for AS. Spinal measurements were compared with axial and peripheral forms of PsA, and the ability of the techniques to discriminate between the 2 forms of PsA was analyzed using the Mann-Whitney U test and the area under the receiver operating characteristic (ROC) curve. A logistic regression model was used to determine the best measurements for evaluating axial PsA. Finally, the results of measurements for axial PsA were compared with those for AS. RESULTS: Of the 100 PsA patients, 46 met the classification criteria for axial PsA, which presented more severe spinal measurement assessments compared with peripheral PsA. Modified Schober test, lumbar side flexion, chest expansion, and cervical rotation measurements performed best under the ROC curve. Modified Schober test, lumbar side flexion, and cervical rotation were the more suitable measurements for assessing axial PsA. There were only minor differences between axial PsA and AS. CONCLUSION: The spinal measurements used to evaluate AS performed well to assess spinal involvement in PsA. These measurements, notably the modified Schober test, lumbar side flexion, and cervical rotation, should be used in daily clinical practice to assess PsA patients with spinal involvement.